From b39d851dcbf0d19b6c97f77b402511041e66ab20 Mon Sep 17 00:00:00 2001 From: Ian Lepore Date: Sun, 24 Nov 2019 21:08:56 +0000 Subject: [PATCH] When doing ARM stack unwinding as part of stack_save(9), do not search loaded modules (pass 0/false for the can_lock arg). Searching the unwind info in modules acquires an exclusive sxlock, and the stack(9) functions can be called in a context where unbounded sleeps are forbidden (such as from the witness checkorder code). Just ignoring the existence of modules in stack_save() is not ideal, so I'm looking for a better solution, but this commit will make it possible to boot an ARM kernel with WITNESS enabled again, until I get something better. PR: 242200 --- sys/arm/arm/stack_machdep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/arm/arm/stack_machdep.c b/sys/arm/arm/stack_machdep.c index 54f8b5e3d830..75d631f778e7 100644 --- a/sys/arm/arm/stack_machdep.c +++ b/sys/arm/arm/stack_machdep.c @@ -40,7 +40,7 @@ stack_capture(struct stack *st, struct unwind_state *state) { stack_zero(st); - while (unwind_stack_one(state, 1) == 0) { + while (unwind_stack_one(state, 0) == 0) { if (stack_put(st, state->registers[PC]) == -1) break; }